Going to micro adjust my 7D+sigma 150-600

[Chilt]

Hey guys, going to micro adjust my sigma lens today, I mainly use it at 500mm how far back from the target should I stand? I says I should stand 25m away but I find it quite hard to tell what’s in focus even at f6.3, now I’d prefer to do the on camera adjustment instead of going into the sigma software. I also have a calibration chart.

I find close up at like 10m my lens is bang on, but when I get further away like 20+ metres the focus really drops off. Any ideas?

Any help would be great.
All the best
Nick

 

[Brazo]

500mm x 2.5 = 1250. 1250/100 is a 12.5m distance to target.

Edit... forgot to add in the crop factor so 500 x 1.6 so the final result is actually 20m.


But if just doing the one distance it’s best to adjust it at the focal distance you use the most. I’ve just done a Sigma 40 1.4 and simply chose my preferred portrait distance.

What you’ve already found with this lens is that the minimum focusing distance has one value and the infinity focus has another, hence the dock I’m afraid is required as anything else will be a compromise.

I do a lot of lens calibration and use Reikan Focal software really helps with the process.

The whole calibration process is a soul destroying joyless experience that requires lots of practice, patience and hours of wasted time!